<?php
error_reporting(E_ALL);
$servername = "localhost";
$username = "root";
$password = "divyesh";
$dbname = "my_data";

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

$data = file_get_contents('data.txt');
$data = json_encode($data);
$data = json_decode($data);
// $data = addslashes($data);
// $data = trim($data);
// $data = mysqli_real_escape_string($conn,$data);
// echo "<pre>"; var_dump($data);

$sql = "INSERT INTO device_update VALUES  {$data}" ;

if ($conn->multi_query($sql) === TRUE) {
    echo "New records created successfully";
} else {
    echo "Error: " . $sql . "<br>" . $conn->error;
}

$conn->close();

?>

[{"id":"1","device_id":"1","device_ip":"172.16.1.65","old_version":"2.3","new_version":"2.4","status":"success","request":"Added MAC Address in OPT1, fd","response":"Added MAC Address in OPT1, fddfd","created_at":"2019-03-06 12:16:40"},{"id":"2","device_id":"1","device_ip":"172.16.1.67","old_version":"2.3","new_version":"2.4","status":"success","request":"Added MAC Address in OPT1, fdjklyuiyu","response":"Added MAC Address in OPT1, fddfdgftrfg","created_at":"2019-03-06 12:16:40"}]

string(485) "[{"id":"1","device_id":"1","device_ip":"172.16.1.65","old_version":"2.3","new_version":"2.4","status":"success","request":"Added MAC Address in OPT1, fd","response":"Added MAC Address in OPT1, fddfd","created_at":"2019-03-06 12:16:40"},{"id":"2","device_id":"1","device_ip":"172.16.1.67","old_version":"2.3","new_version":"2.4","status":"success","request":"Added MAC Address in OPT1, fdjklyuiyu","response":"Added MAC Address in OPT1, fddfdgftrfg","created_at":"2019-03-06 12:16:40"}]"
Error: INSERT INTO device_update VALUES  [{"id":"1","device_id":"1","device_ip":"172.16.1.65","old_version":"2.3","new_version":"2.4","status":"success","request":"Added MAC Address in OPT1, fd","response":"Added MAC Address in OPT1, fddfd","created_at":"2019-03-06 12:16:40"},{"id":"2","device_id":"1","device_ip":"172.16.1.67","old_version":"2.3","new_version":"2.4","status":"success","request":"Added MAC Address in OPT1, fdjklyuiyu","response":"Added MAC Address in OPT1, fddfdgftrfg","created_at":"2019-03-06 12:16:40"}]
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '[{"id":"1","device_id":"1","device_ip":"172.16.1.65","old_version":"2.3","new_ve' at line 1